Apparatus for winding coils of metal strip material



Oct. 22, 1968 ,w. BRUNS ETAL APPARATUS FOR WINDING COILS OF METAL STRIP MATERIAL 4 Sheets-Sheet 1 Filed July 9, 1965 s Y m @M T C R E T VWB T m s A m mm" TC m5 MW 82 $1.18 I f O\ N MN\ 09 Oct. 22, 1968 E.w. BRUNS ETYAL APPARATUS FOR WINDING C'OILS OF METAL STRIP MATERIAL 4 Sheets-Sheet '2 Filed July 9, 1965 FIG-3 44 (fed 0a. 22. 1968 W. BRUNQQ AL 3,406,924

APPARATUS FOR WINDING COILS OF METAL STRIP MATERIAL Filed July 9, 1965 v 4 Sheets-Sheet F IG-6 4 25 34 I33 0 I3 I I22.

FIG -7 122 2 E.W. BRUNS ET AL 3,406,924

SOILS OF METAL STRIP MATERIAL 4 Sheets-Sheet 4 Oct. 22, 1968 APPARATUS FOR WINDING Filed July 9, 1965 United States Patent @flice 3,406,924 Patented Oct. 22, 1968 3,406,924 APPARATUS FOR WINDING COILS F METAL STRIP MATERIAL Elton W. Bruns and Richard E. Black, New Bremen, Ohio,

assignors to Starnco, Inc., New Bremen, Ohio, a cor poration of Ohio Filed July 9, 1965, Ser. No. 470,301 Claims. (Cl. 24256.4)

ABSTRACT OF THE DISCLOSURE A slitter-winder wherein the plurality of separate strips formed by the slitting operation are wound onto corresponding cores mounted on a cantilevered mandrel be tween fiat drive rings fixed for rotation with the mandrel. The drive rings are axially slidable on the mandrel and frictionally engage the ends of the cores by controlled pressure applied axially against the end of the entire assembly of cores and interspaced drive rings mounted on the mandrel.

This invention relates to apparatus for handling coils of metal strip, and more particularly, to apparatus for unwinding a coil of single metal strip for slitting to form a plurality of separate strips of predetermined width and for rewinding the strips into individual coils while maintaining continuous tension in each strip durng the rewinding operation.

In the continuous production of rolling of metal strip, and especially with wider strips, it is difficult to prevent the forming rolls of a rolling mill from bowing by a slight amount. This is caused in part by the weight of the forming rolls but primarily by the enormous radial loading on the rolls as they progressively compress the metal strip to reduce its thickness. As a result, the metal strip which is formed usually varies in cross-sectional thickness with the center portion of the strip being a few thousandths thicker than the edge portions. Furthermore, as the strips increase in width, usually the differential in thickness across each strip also increases. Thus when the single strip is coiled, the center portion of the single strip has a tendency to increase in diameter at a faster rate than the edge portions which results in producing greater tension in the center portion of the strip within the coil.

When the single coiled strip is subsequently run through a slitting operation to form a plurality of separate strips, it has been found that the stresses within the strip are relieved, and in addition, the strips formed from the center portion of the single strip will have a slightly greater thickness than those strips formed from the edge portion. Thus when each of these separate strips are rewound on a common mandrel into separate coils, the tension in the strips forming the center coils of the mandrel is substantially greater than the tension in the strips forming the outer or end coils.

It is desirable to maintain suiiicient tension in each of the strips forming the separate coils during the rewinding operation so that the coils are not loosely formed and will not collapse or telescope after they are removed from the rewinding mandrel. Thus a common procedure is to provide a frictional resistance or drag on each of the separate strips between the slitting and rewinding operations. This drag develops a progressively increasing slack in the strips formed from the edge portions of the single strip, and commonly, a large pit upwards of twenty feet in depth is provided in which to suspended loops of the strips as the slack progressively increases.

In view of the present trend toward larger coil diameters for obtaining more efiicient handling of the strips and more efficient use of the machines which subsequently receive the metal strips, it has been found necessary to construct deeper and deeper pits. Furthermore, it is also common procedure to employ a radially expandable mandrel for rewinding the strips into coils. These mandrels are not only complicated in construction, since they must expand and retract radially so that the coils can be removed therefrom, they also commonly employ clamping slots for gripping the leading ends of the separate strips. These slots have been found undesirable since the end portion of each strip must be bent for insertion within the slot, and this bend produces a slight bump in the coil after the first wrap, which tends to mark several successive wraps of the strips.

Another common problem encountered with the rewinding of separate metal strips on a single expandable mandrel is that adjacent strips have a tendency to interweave as the strips are rewound into coils. This causes difiiculty in removing the coils from the rewinding mandrel. In an attempt to solve this problem, separating disks have been employed between adjacent coils, but this has been found to result in undesirable rubbing between the disks and the edges of the strips.

In general, the present invention is directed to simplified and less expensive apparatus which maintains continuous tension in each of the separate strips during the rewinding operation, does not require the construction of pits between the slitting and rewinding stations and furthermore eliminates the problem of interweaving between strips.

Accordingly, it is one primary object of the present invention to provide apparatus which slits a single metal strip from an unwinding coil to form a plurality of separate strips each having a predetermined width, and rewinds the separate strips into corresponding coils on a common mandrel while maintaining continuous constant tension in each strip so that all of the separate rewound coils may be conveniently handled without collapsing or telescoping.

It is also an object to provide apparatus which can receive a single metal strip having variations in thickness across its width, slit the single strip to form a plurality of separate strips, and then rewind the separate strips into coils While spacing adjacent strips apart from each other by a slight amount to prevent interweaving between adjacent strips and difficulty in separating the coils.

A further object of the invention is to provide apparatus as outlined above which includes a simply constructed rewinding mandrel for frictionally driving a separate cylindrical core for each rewinding coil by rotatably slipping within the cores to provide relative rotation or slip among the cores as required for maintaining a tension in each of the separate strips according to the difference in average thickness among the strips.

Still a further object of the invention is to provide apparatus as outlined above wherein coils of different widths can be easily formed on a single mandrel at the rewinding station and can be easily removed from the mandrel.

It is also an object of the invention to provide apparatus which is adapted to rewind separate metal strips onto relatively inexpensive cylindrical cores capable of being retained within the coils for handling without damage or may be easily removed, as desired.

As another object, the present invention provides an apparatus as outlined above wherein the frictional drive of each of the cylindrical cores mounted on the rewinding mandrel is increased proportionally to the increase in diameter of the rewinding coils to provide substantially constant rewinding tension within the strips being rewound.

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings:

FIG. 1 is a general elevational view of apparatus constructed in accordance with the invention and comprising slitting and rewinding stations;

FIG. 2 is a corresponding'plan view'of the apparatus shown in FIG. '1;

FIG. 3 is a vertical section of the slitting apparatus shown in FIG. 1;

FIG. 4 is a fragmentaryplan view showing somewhat schematically the forming, speading and rewinding of the separate metal strips which are'rewound into coils at the rewinding station in FIG. 1;

FIG. 5 is a somewhat exaggerated elevational view of the adjustable bow rolls employed for fanning or spreading the separate metal strips leading from the slitting station;

FIG. 6 is a section of the line 6-6 of FIG. 8 showing the mecahnism in the rewinding mandrel for frictionally driving the plurality of rewinding cores;

FIG. 7 is a section on the line 77 of FIG. 8 showing the driving mechanism in retracted position for mounting the cores or removing the rewound coils;

FIG. 8 is an end view looking from right to left in FIG. 6 and partially in section on the line 88 of FIG 6;

FIG. 9 is a plan view of the supporting and driving device for the rewinding mandrel;

FIG. 10 is a detailed elevational view of the mechanism which assures predetermined slight separation among the metal strips at the rewinding station and for sensing the diameters of the rewinding coils;

FIG. 11 is a detailed sectional view of an end portion of the disk members shown in FIG. 10 for guiding and maintaining the separation among the metal strips;

FIG. 12 is an axial end view of a collapsible core adapted for use when it is desired to remove the core from the rewound coil; and

FIG. 13 is a fragmentary section similar to FIG. 6- and showing a modified friction driving mechanism for rotating the slip cores.

Referring to the drawings, which illustrate a preferred embodiment of the invention, the apparatus shown generally in FIGS. 1 and 2 basically provides four stations, an unwinding station A, slitting station B, spreading station C and a rewinding station D. Positioned at the unwinding station A is a support housing 15 in which are mounted suitable bearings for rotatably supporting a cantilevered unwinding mandrel 17 on which is mounted an unwinding coil 19 of single metal strip 20. A motor 22 is provided to drive a suitable gear reduction unit enclosed within the housing 15 which in turn drives the unwinding mandrel 17. As mentioned above, the thickness of the single metal strip commonly varies across the width of the strip by several vthousandths of an inch and is usually thicker in the center portion. This single strip 20 is fed from the coil 19 into the nip 23 defined between a pair of guide rolls 24 which are rotatably supported one above the other On the frame member 26. A tachometer 27 is driven by one roll 24 to determine precisely the speed of travel of the strip 20.

The rolls 24 guide the single strip 20 into the circular shearing knives or members 29 which are carried on a pair of arbors 30 rotatably supported by a frame 32 at the slitting station B and driven by a suitable drive motor 36. The plurality of separate metal strips 40 which are sheared from the single strip 20 by the shearing members 29 travel to a pair of bowed rolls 42 and 43 which are supported by a frame 44 at the spreading station C and spread the strips to define slight separations or slots 45 between adjacent strips 40. The separation is desirable especially during high speed operation of the apparatus to prevent adjacent strips 40 from rubbing together and interweaving at the rewinding station D.

The degree of the bow in the rolls 42 and 43 is variable and is controlled by operation of the corresponding hydraulic jacks 46 which compress the rolls axially to provide the how. The degree of how in the. rolls 42 and 43 has been-exaggerated in FIG. 5 to illustrate themanner in which the separate strips 4,0=-are separated by the bowed rolls. The lower bowed roll 42 providesthe initial sperading of the strips 40, and the upper bowed roll 43 stops the spreading so that the separate strips 40 travel in parallel relationship to the rewinding station D.

Referring to FIGS. 3 and 4, the trimmings 51 sheared from the edge of the single metal strip 20 by the end shearing members 29"are received Within a chute 52 which directs the trimmings to a suitable scraping mechanism (not shown) for cutting them into small pieces for further processing. As also shown in FIG. 3, the upper bowed roll 43 is rotatably supported by a carriage 55 which is adapted to travel along the inclined guideway 57 mounted on the supporting frame 44. The position of' the carriage 55 is controlled by a pressure cylinder 60 having a piston rod 62 pivotally connected to the'carriage 55 by the pin 63.

Also rotatably supported by the carriage 55 is a guide roll 64 which provides the desired degree of wrap of the separate strips 40 around the upper bowed roll 43. Thus the width of the slots 45 between the strips 40 can be controlled both by the relative spacing between the bowed rolls 42 and 43 and by operating the jacks 46 for controlling the degree of bow in the rolls 42 and 43. With some strips it may not be necessary or desirable to use the bowed rolls 42 and 43, as for example, when the thickness of the strip 20 exceeds .032 inch. In these situations, the separate strips 40 are directed to the rewinding station D along a path 66 as shown in FIG. 1.

Rotatably supported at the rewinding station D is a cantilevered rewinding mandrel 70 which includes a spindle portion 71 (FIG. 9) removably mounted within a tubular support casing 73 which is in turn rotatablysupported in a housing 75 by the bearings 77 and 78. The spindle portion 71 of the mandrel 70 preferably has a tapered portion 80 which engages and is keyed within a corresponding tapered opening 81 formed within the tubular support casing 73 to provide a tight collet-type fit between the casing and the mandrel 70 when the nut 82 is tightened against the bracket 83 mounted on the end of the casing 73.

As shown in FIGS. 6 and 9, the rewinding mandrel 70 and its spindle portion 71 are provided with an axially extending opening 84 through which extends a rod 86. The inner end of the rod 86 (FIG. 9) projects from the end of the spindle portion 71 and is connected to the piston rod 88 extending from a double action fluid pressure cylinder 90. By operation of the cylinder 90, the rod 86 is reciprocated a few inches within the opening 84; Rigidly mounted on the casing 73 by the key 91 and enclosed within the housing 75 is a gear 92 which is driven by a suitable variable speed drive motor 94 through the stub shaft 96 on which is mounted a drive pinion 98. Thus by controlling the speed of the motor 94, the speed of rotation of the mandrel 70 is controlled.

As shown in FIG. 6, the elongated mandrel 70 is formed basically as one solid piece and carries a sleeve bearing 104- which rotatably supports the outer end of the rod 86. Mounted on the outer end of the mandrel 70 are a pair of pins 107 which guide an X-shaped support member 108 mounted on the end of the rod 86 by the threaded connection 111. Also guiding the support member 108 is a cylindrical sleeve 114 which is retained within a counterbore 116 formed on the outer end of the mandrel 70. I

A series of cars 118 (FIG. 8) are welded to the inner surface of the cylindrical casing 114- 'and extend inwardly to receive a series of four bolts 120 which are threaded into the end portion of the mandrel 70 to secure the cas ing 114 rigidly within the counterbore 116. A series of four slots 122. are formed radially in the casing 114 adjacent the end of the mandrel 70. Adapted to extend and retract through the slots 122. are a corresponding series of dogs 125 which are pivotally mounted on the support member 108 by the pins 126. The torsion springs 128 are provided to bias the dogs 125 outwardly through the slots 122 when the support member 108 is pulled inwardly by the rod 86. However, when the rod 86 is extended, the support member 108 moves axially within the casing 114 causing the dogs 125 to be cammed inwardly around the edge 130 of the slots 122 and collapse into the casing 114.

A drive ring 123 (FIG. 6) is mounted on the inner end of the mandrel 70 adjacent the annular shoulder 134 and is adapted to engage the radial end surface of an inner cylindrical core 135 mounted on the outer cylindrical surface of the mandrel 70. As illustrated in FIG. 6, the number of cylindrical cores 135 mounted on the mandrel 70 corresponds to the number of separate metal strips 40 which lead from the spreading station C to the rewinding station D, and each core 135 is adapted to receive the corresponding leading ends of a strip 40 which preferably is secured to the outer surface of the core 135 as by tape.

Preferably, the cylindrical cores 135 are formed from a relatively inexpensive phenolic impregnated fiber material, but other materials such as paper, wood, cardboard, metal or the like may be used. The inner diameter of each of the cores 135 is slightly greater than the outside diameter of the mandrel 70, as for example, a clearance of ,6, on the diameter has been used successfully and enables the cores 135 to be easily mounted on and removed from the mandrel 70.

Mounted between each adjacent pair of cores 135 is a slip ring 140 having a pair of diametrically opposed tangs 142 (FIG. 8) which are received within a corresponding pair of axially extending slots 144 formed in the outer surface of the mandrel 70 so that the slip rings 140 are positively carried by the mandrel 70 when it is rotated by the drive motor 94. Preferably, the thickness of each of the slip rings 140 corresponds to the width of the slots 45 defined between the parallel separate metal strips 40. Thus as the strips 40 are rewound into separate coils 150 on the corresponding cores 135, a radially extending space is provided between the coils 150 to prevent overlapping and interweaving between the strips during the rewinding operation.

The axial length of each of the cores 135 is selected according to the width of the corresponding strip 40 which is received by the core for rewinding. After the cores 135 are mounted on the mandrel 70 separated :by the slip rings 140, a second drive ring 152 is mounted on the mandrel adjacent the end surface of the end core 135. The drive rings 133 and 152 are also provided with diametrically opposed tangs 153 (FIG. 8) so that the rings rotate with the mandrel 70 along the slip rings 140. The cores 135, slip rings 140 and drive ring 152 are positioned on the mandrel 70 while the dogs 125 are retracted as shown in FIG. 7. After the cores and slip rings are assembled, the pressure cylinder 90 is energized to pull the rod 86 inwardly, causing the support member 108 to shift to the position shown in FIG. 6, whereupon the torsion spring 128 causes the dogs 125 to pivot outwardly and to engage the radial end surface of the end drive ring 152.

After the leading ends of the separate metal strips 40 are attached to the outer surfaces of the corresponding cores 135, preferably by a suitable tape, and the strips are given approximately 1% wraps around the core 135, the unwinding, slitting and rewinding operations are started by energizing the motors 22, 36 and 94 respectively, which starts the forming of the rewinding coils 150. During this rewinding operation, tension is maintained in the rod 86 by the pressure cylinder 90 so that the radial end surfaces of the cores are compressed firmly against the radial surfaces of the slip rings and the end drive rings133 and 152. This provides an end friction drive of each of the cores 135 causing the cores 135 to rotate with the mandrel 70.

As the rewinding coils are formed on the corresponding cores 135 at the rewinding station D, the outer diameter of the center coils on the mandrel 70 will normally increase at a faster rate than the end coils, due to the variations in metal thickness as explained above. It has been found desirable to rotate the mandrel 70 at a slightly higher speed than is necessary to rewind the outside strips 40 on the corresponding out-er cores 135 so that all of the cores slip somewhat in relation to the mandrel 70. This has been found to maintain a continuous tension in all of the separate strips 40, but it becomes apparent that the inner cores 135 mounted on the mandrel 70 will slip in relation to the outer cylindrical surface of the mandrel 70 more than the outer cores 135.

As shown in FIG. 10, the precise separation or slots 45 between adjacent strips 40 is held with precision by a series of circular disks (FIG. 11) which are carried on a tubular arbor 162 rotatably mounted on a shaft 165 by the end bearings 167. The spacing between the disks 160 is determined by the cylindrical spacing members 166 which have axial lengths coresponding to the widths of the separate metal strips 40. A nut 168 is mounted on the end of the arbor to retain the disks 160, spacing members 166 and end collars 169. The thickness of each of the disks 160 preferably corresponds with the thickness of the slip rings 140 and the slots 45 between the strips 40 as provided by the bowed rolls 42 and 43.

The end portions 170 of the shaft 165 are mounted on the ends of a pair of arms 171 (FIG. 2) and are retained thereon by a plate 172 extending across flats 173 formed on the end portions 160. The arms 171 are rotata'bly supported on a frame 174 by the shaft 175. Thus as the rewinding coils 150 increase in diameter, the arms 171 rotate upwardly so that the disks 160 follow the increasing diameter of the coils 150. As shown in FIG. 10, preferably the axis of the arbor 162 is maintained slightly in front of the tangent line 176 where the separate strips 40 lead onto the coils 150. This has been found desirable to maintain the precise separation between the coils 150 without causing binding between the disks 160 and the edges of the strips 40.

To prevent the weight of the arms 171, arbor 162, shaft 165 and disks 160 from resting against the outer surface of the coils 150 as they are wound, these components are counterbalanced by a pressure cylinder 177 (FIG. 10) mounted on the frame 174. The piston 178 extending from the pressure cylinder is pivota'lly connected by the pin 181 to a support arm 182 rigidly mounted on the shaft along with the arms 171 by a suitable key (not shown). A hand operated lever 186 is pivotally connected to one of the arms 171 and extends downwardly for engaging a stud 190' within the notch 192 when the arms 171 are moved to their uppermost position. This lever provides a safety catch in case the fluid supply for the pressure cylinder 176 fails, and thereby prevents the arms 171 and disks 160 from dropping.

As the rewinding coils 150 increase in diameter, it has been found desirable to increase the frictional drive forces between each of the slip rings 140, drive rings 133 and 152 and the adjacent cylindrical cores 135. Preferably, this increase is provided substantially proportionally to the increase in diameter of the coils 150. Thus by increasing the pressure within the cylinder 90, the force of the dogs 125 acting against the drive ring 152 is increased.

For this control, the movement of the arms 171 is sensed by a rheostat 200 (FIG. 10) which is mounted on the frame 174 and is controlled by the rotation of the rheostat spindle 202 connected for direct rotation with the shaft 175 by a timing belt 205 linking the pulleys 206 and 207. Thus as the arms 170 move upwardly with an increase in diameter of the rewinding coils 150, the rheostat 202 controls a servo valve system (not shown) which increases the pressure within the fluid cylinder 90. This increasing pressure, in turn, provides an increasing axial compression force between the end drive rings 133 and 152 causing an increase in the frictional drive of the cores 135 by the slip rings 140.

After the slitting and rewinding operation is completed, the pressure cylinder 90 is actuated causing the rod 86 to extend outwardly and the dogs 125 to be retracted to the position shown in FIG. 7. The separate coils 150 are then removed from the mandrel 70 along with the drive ring 152 and slip rings 140.

For some subsequent uses of the separate strips 40, it is desirable to remove the cores 135 from the rewound coils 150. For this purpose, a collapsible core 215 (FIG. 12) is used. This core is formed with an axially extending slot 216 and a cylindrical axially extending opening 218 which receives a pin 220. Thus when it is desirable to remove the core 215 from a coil 150 after the rewinding operation, the pin 220 is driven out of the opening 218, allowing the core 215 to collapse by the width of the slot 216 which is sufficient for conveniently removing the core 215 from the coil 150.

A modified embodiment of the present invention is shown in FIGURE 13 where in place of the drive ring 152 shown in FIG. 6, a pair of drive rings 225 and 226 are mounted on the end portion of the mandrel 70 after the cores 135 are placed thereon and are connected by a series of circumferentially spaced bolts 228 having heads 229. The bolts 228 extend through holes in the ring 226 and are secured within corresponding threaded openings 230 within the ring 225 so that the ring 226 can slide on the bolts 228 relative to the ring 225.

Surrounding each of the bolts 228 and spaced between the rings 225 and 226 are a corresponding series of compression springs 232 which normally press the ring 226 against the heads 229 of the bolts 228. After the cores 135 are positioned on the mandrel 70, the assembled unit of the rings 225 and 226 connected by the compression springs 232 and bolts 228 is mounted on the end portion of the mandrel so that when the dogs 125 are extended, they engage the end face of the ring 226. Thus when the pressure cylinder 90 (FIG. 9) is actuated to retract the rod 86, the dogs 125 move the ring 226 towards the ring 225, thereby compressing the springs 232 which, in turn, exert an axial force against the cores 135.

It has been found that for rewinding some strips of material, the force exerted by the springs 232 will provide sufficient pressure between the drive ring 225 and the end core 135 without requiring continuous automatic control of the pressure cylinder 90. Thus with the drive mechanism shown in FIG. 13, it is unnecessary to increase continuously and progressively the pull on the rod 86 as the rewinding coils 150 increase in diameter. Instead, the friction drive of the cores 135 provided by the compression springs 232 will produce a continuous tension in the strips during the rewinding operation. With some strips, however, depending on the type of material and thickness, it may be desirable to make periodical manual adjustments of the pressure within the cylinder 90 to provide incremental or step by step axial movement of the dogs 125 as the coils increase in diameter to increase the force exerted by the drive ring 225 on the slip cores 135 in generally the same manner as automatically provided by the rheostat 200 described above.

From the drawings and the above description it can be seen that the apparatus of the present invention provides several desirable features and advantages. To summarize, the apparatus maintains continuous tension in each of the separate metal strips 40 as they are rewound into coils regardless of variation in metal thickness across the width of the single metal strip 40. Furthermore, the separate strips 40 are provided with a uniform separation at all times during the rewinding operation so that there 8 is no possibility of rubbing or interweaving of the strips 40 as they are rewound into coils. These advantages are accomplished by an inexpensively constructed rewinding mechanism which includes the solid mandrel and slip rings 140 for frictionally driving the separate cores on which the single metal strips 40 are rewound.

In addition, the cylindrical cores are easily mounted on the mandrel 70 and the rewound coils 150 can be easily removed from the mandrel. It is also an additional feature that the frictional driving force between the cores 135 and the slip rings can be progressively increased corresponding with an increase in diameter of the rewinding coils. Thus a continuous tension can 'be maintained within the separate strips 40 during the entire rewinding of the coils which, in turn, prevents telescoping or collapsing of the rewound coils.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. Apparatus for unwinding and slitting a single metal strip arranged in a coil to form a plurality of separate strips each having a predetermined width and for rewinding the strips into separate coils while maintaining a continuous tension in each strip regardless of the variation in metal thickness across the width of the single strip, said apparatus comprising means for rotatably supporting the coil of a single strip at an unwinding station, means for slitting the single strip into a plurality of separate strips, drive means for feeding the single strip through said slitting means, a rotatably supported mandrel defining a rewind station, a corresponding plurality of cylindrical core members mounted for relative rotation on said mandrel and adapted to receive corresponding leading ends of the separate strips formed by said slitting means, each said core member having opposite radially extending end surfaces, a drive ring member positively mounted on said mandrel between each adjacent pair of of said core members and having drive surfaces frictionally engaging the corresponding said end surfaces of said core members, power operated means for driving said mandrel at a speed slightly faster than the core member speed required for rewinding the thinnest strip to provide relative rotational slip between each said core member and its corresponding said drive ring members as the rewound coils are formed to compensate for the differences in diameters of the coils caused by the the variation in metal thickness among the strips, and means on said mandrel adjacent the end said core members for pressing said core members axially against said drive ring members as the coils are formed to provide a continuous tension in each of the strips so that the coils formed by the strips are Wound with sufficient tightness to enable handling without collapsing or telescoping.

2. Apparatus as defined in claim 1 including a pair of variable bowed rolls spaced between said slitting means and said mandrel to fan out the separate strips and return them to parallel spaced relation so that adjacent coils formed on said core members are spaced apart by a slight amount to prevent interleaving of the strips forming said adjacent coils.

3. Apparatus as defined in claim 1 including a circular spacing disk for each said drive ring member and corresponding said disk and said ring members having substantially equal thickness, and means movably supporting said disk between said strips adjacent the outer surface of the rewinding coils to prevent interleaving of adjacent strips forming said coils.

4. Apparatus for unwinding and slitting a single metal strip arranged in a coil to form a plurality of separate strips each having a predetermined width and for rewinding the strips into separate coils while maintaining continuous tension in each strip regardless of the variation in metal thickness across the width of the single strip, said apparatus comprising means for rotatably supporting the coil of single strip at an unwinding station, means for slitting the single strip into a plurality of separate strips, drive means for feeding the single strip through said slitting means, a rotatably supported mandrel defining a rewind station, a corresponding plurality of cylindrical core members mounted for relative rotation on said mandrel and adapted to receive corresponding leading ends of the separate strips formed by said slitting means, a ring member positively mounted on said mandrel between each adjacent pair of said core members and having opp'osite driving end surfaces frictionally engaging the surfaces of the adjacent said core members, power operated means for driving said mandrel at a speed slightly faster than the core member speed required for rewinding the thinnest strip so that the core members slip in relation to said ring members as the rewound coils are formed to compensate for the difference in diameter of the coils caused by the variation in metal thickness among the strips, and means adjacent the end said core members on said mandrel for applying axial pressure between said ring members and adjacent said core members during forming of the coils to provide continuous tension in each of the strips so that the coils formed by the strips are wound with suflicient tightness to enable handling without collapsing or telescoping.

5. Apparatus for slitting a single strip of material to form a plurality of separate strips each having a predetermined width and for winding the strips into separate coils while maintaining continuous tension in each strip regardless of the variation in thickness across the Width of the single strip, said apparatus comprising means for slitting the single strip into a plurality of separate strips, a mandrel, means supporting said mandrel in a cantilevered position, power operated means for driving said mandrel, a plurality of cylindrical core members mounted for relative rotation on said mandrel and adapted to receive corresponding leading ends of the separate strips formed by said slitting means, a plurality of generally flat thin drive rings mounted on said mandrel for positive rotation therewith with at least one said ring located between each adjacent pair of said core members, each said ring being axially slidable on said mandrel and having opposite driving surfaces frictionally engaging the end surfaces of the adjacent said core members so that the core members slip in relation to said rings as the coils are formed, and means adjacent the end said core members on said mandrel for applying axial pressure against the entire assembly of said rings and adjacent said core members during forming of the coils to provide continuous tension in each of the strips so that the coils formed by the strips are wound with suflicient tightness to enable handling without collapsing or telescoping.

6. Apparatus as defined in claim including a removable annular collar mounted on the end portion of said mandrel adjacent the end surface of the end said core member, and means including a fluid pressure cylinder for applying a variable axial force against said collar to vary the frictional drive between said driving end surfaces of each said ring member and the adjacent end surfaces of said core members.

7. Apparatus for unwinding and slitting a single metal strip arranged in a coil to form a plurality of separate strips each having a predetermined width and for rewinding the strips into separate coils while maintaining continuous tension in each strip regardless of the variation in metal thickness across the width of the single strip, said apparatus comprising means for rotatably supporting the coil of single strip at an unwinding station, means for slitting =the single strip into a plurality of separate strips, drive means for feeding the single strip through said slitting means, a pair of bowed rolls for receiving the strips from said shear means to spread adjacent strips and to return them to parall-al spaced relation, pressure cylinder means for varying the degree of how of said rolls to. control the amount of separation between adjacent strips, means for adjustably spacing one of said rolls in relation to the other for also providing control of the amount of separation between adjacent said strips, a rotatably supported mandrel defining a rewind station, power operated means for driving said mandrel, a corresponding plurality of cylindrical core members mounted for relative rotation on said mandrel and adapted to receive corresponding leading ends ofthe separate strips leading from one of said bowed rolls, each said core member having opposite radial end surfaces, a ring member positively mounted on said mandrel between each adjacent pair of said core members and having opposite radial drive surfaces frictionally engaging said end surfaces of the adjacent said core members and adapted to provide relative rotational slip among said core members as the rewound coils are formed to compensate for the difference in diameter of the coils caused by the variation in metal thickness among the strips, each said ring member having an axial thickness equal to the space betwen the corresponding adjacent pair of strips as produced by said bowed rolls, and means adjacent the end said core members on said mandrel for pressing said core members axially adjacent said ring members to provide continuous tension in each of the strips so that the coils formed by the strips are wound with sufficient tightness to enable handling without collapsing or telescoping.

-8. Apparatus for unwinding and slitting a single metal strip arranged in a coil to form a plurality of separate strips each having a predetermined width and for rewinding the strips into separate coils while maintaining continuous tension in each strip regardless of the variation in metal thickness across the width of the single strip, said apparatus comprising means for rotatably supporting the coil of single strip at an unwinding station, means for slitting the single strip into a plurality of separate strips, drive means for feeding the single strip through said slitting means, a rotatably supported mandrel defining a rewind station and having means defining at least one axially extending slot formed in its outer surface, a plurality of cylindrical core members mounted for relative rotation on said mandrel and adapted to receive corresponding leading ends of the separate strips formed by said slitting means, each said core member having opposite end surfaces, a drive ring member mounted on said mandrel between each pair of adjacent said core members, said drive ring members each having means extending into said slot to provide positive rotation of said ring members with said mandrel and axial movement of each said ring members on said mandrel, each said drive ring member including means for frictionally engaging and driving said end surfaces of said core members, power op'erated means for driving said mandrel at a speed slightly faster than the core members speed required for rewinding the thinnest strip so that the core members slip in relation to said ring members as the rewound coils are formed to compensate for the diiference in diameter of the coils caused by the variation in metal thickness among the strips, and means for applying uniform axial pressure between said ring members and adjacent said core members as the coils are formed to provide continuous tension in each of the strips so that the coils formed by the strips are wound with suflicient tightness to enable handling without collapsing or telescoping.

9. Apparatus as defined in claim 8 wherein said means for applying said axial pressure includes a series of dog members adapted to engage an end drive ring mounted on said mandrel, axially movable rod means extending through said mandrel for actuating said dog members from a retracted position for loading and unloading said mandrel to an extended position for applying pressure to said drive ring, fluid cylinder means connected to said rod means, and means for automatically increasing the pressure within said fluid cylinder means as the coils increase in diameter to provide a substantially constant tension in each said strip.

10. Apparatus as defined in claim 8 wherein said means for applying said axial pressure includes a pair of spaced drive rings mounted on said mandrel, a plurality of annularly arranged compression springs positioned between said drive rings, and means on said mandrel for moving one of said rings toward the other said ring for compressing said springs to provide a continuous axial drive force against said core members during the rewinding of the coils.

12 References Cited UNITED STATES PATENTS 2,526,029 10/1950 Judelson 242563 2,855,161 10/1958 Ganz et a1. 24272 3,010,671 11/1961, Brown 242569 3,032,914 5/1962 Valle 24256.9 3,061,226 '10/ 1962 Kegg 24256.9 X 3,106,365 10/1963 Karr 24256.4 X 3,266,743 8/1966 Moser et a1. 24256.4

GEORGE F. MAUTZ, Primary Examiner.

Patent No 3 ,406 ,924

U.S. DEPARTMENT OF COMMERCE PATENT OFFICE Washington, D.C. 20231 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION October 22, 1968 Elton W. Bruns et a1.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 54, "of" should read on Column 3, line 18, "speeding" should read spreading Column 4, line 5, "interweaving" should read interleaving line 13, "sperading" should read spreading Column 5, line 16, "123" should read 133 Column 12, after line 10, insert Foreign Reference 11,998 1908 Great Britain Signed and sealed this Qth day of December 1969.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer 

